1. Field of the Invention
The present invention relates to telecommunications and, more particularly, to methods and systems for using a client device location that is provided by an access network for routing an voice-over-packet (VoP) emergency services call from the client device to an appropriate public safety answering point (PSAP).
2. Description of Related Art
The ability to place an emergency services call by dialing 9-1-1 has become widespread throughout the United States. When a 9-1-1 call is placed, it is typically answered at a PSAP. However, there are many PSAPs throughout the United States, each serving a particular area, such as a city, county, or metropolitan area. The public switched telephone network (PSTN) can route a 9-1-1 call to the appropriate PSAP, i.e., the PSAP that servers the caller's area, because the caller's telephone number is associated with a fixed location. The PSAP can also reliably determine the caller's location based on the caller's telephone number.
Increasingly, however, packet networks are being used for voice communications, including emergency services calls. Such voice-over-packet (VoP) networks often route calls that are placed by client devices that can change their point of connectivity to the network. Because of this mobility, client devices and their associated telephone numbers may not be reliably associated with fixed locations. Even so, it is desirable for a user of a client device to be able to dial 9-1-1 from any location and have the call routed through the VoP network to the appropriate PSAP, i.e., the PSAP that serves the user's current location. In addition, it is desirable for the PSAP that answers the call to be able to reliably determine the caller's location, e.g., in order to dispatch assistance to the caller.
Accordingly, there is a need for providing methods and systems for obtaining location information that can be relied upon to route an VoP emergency services call to the appropriate PSAP and to inform the PSAP of the caller's location.